GATE 2022 General Aptitude (GA)
Q.1 – Q.5 Carry ONE mark each.
Q.1
As you grow older, an injury to your _________ may take longer to _________.
(A) heel / heel
(B) heal / heel
(C) heal / heal
(D) heel / heal
Page 1 of 36
Q.2
In a 500 m race, P and Q have speeds in the ratio of 3 ∶ 4. Q starts the race
when P has already covered 140 m.
What is the distance between P and Q (in m) when P wins the race?
(A) 20
(B) 40
(C) 60
(D) 140
Page 2 of 36
Q.3
Three bells P, Q, and R are rung periodically in a school. P is rung every 20
minutes; Q is rung every 30 minutes and R is rung every 50 minutes.
If all the three bells are rung at 12:00 PM, when will the three bells ring
together again the next time?
(A) 5:00 PM
(B) 5:30 PM
(C) 6:00 PM
(D) 6:30 PM
Page 3 of 36
Q.4
Given below are two statements and four conclusions drawn based on the
statements.
Statement 1: Some bottles are cups.
Statement 2: All cups are knives.
Conclusion I: Some bottles are knives.
Conclusion II: Some knives are cups.
Conclusion III: All cups are bottles.
Conclusion IV: All knives are cups.
Which one of the following options can be logically inferred?
(A) Only conclusion I and conclusion II are correct
(B) Only conclusion II and conclusion III are correct
(C) Only conclusion II and conclusion IV are correct
(D) Only conclusion III and conclusion IV are correct
Page 4 of 36
Q.5
The figure below shows the front and rear view of a disc, which is shaded with
identical patterns. The disc is flipped once with respect to any one of the fixed
axes 1-1, 2-2 or 3-3 chosen uniformly at random.
What is the probability that the disc DOES NOT retain the same front and rear
views after the flipping operation?
Front View
Rear View
(A) 0
(B)
1
3
(C)
2
3
(D) 1
Page 5 of 36
Q. 6 – Q. 10 Carry TWO marks each.
Q.6
Altruism is the human concern for the wellbeing of others. Altruism has been
shown to be motivated more by social bonding, familiarity and identification of
belongingness to a group. The notion that altruism may be attributed to empathy
or guilt has now been rejected.
Which one of the following is the CORRECT logical inference based on the
information in the above passage?
(A) Humans engage in altruism due to guilt but not empathy
(B) Humans engage in altruism due to empathy but not guilt
(C) Humans engage in altruism due to group identification but not empathy
(D) Humans engage in altruism due to empathy but not familiarity
Page 6 of 36
There are two identical dice with a single letter on each of the faces. The
Q.7
following six letters: Q, R, S, T, U, and V, one on each of the faces. Any of the
six outcomes are equally likely.
The two dice are thrown once independently at random.
What is the probability that the outcomes on the dice were composed only of
any combination of the following possible outcomes: Q, U and V?
(A) 1
4
(B) 3
4
(C) 1
6
(D)
5
36
Page 7 of 36
Q.8
The price of an item is 10% cheaper in an online store S compared to the price
at another online store M. Store S charges ₹ 150 for delivery. There are no
delivery charges for orders from the store M. A person bought the item from the
store S and saved ₹ 100.
What is the price of the item at the online store S (in ₹) if there are no other
charges than what is described above?
(A) 2500
(B) 2250
(C) 1750
(D) 1500
Page 8 of 36
Q.9
The letters P, Q, R, S, T and U are to be placed one per vertex on a regular convex
hexagon, but not necessarily in the same order.
Consider the following statements:

The line segment joining R and S is longer than the line segment joining
P and Q.

The line segment joining R and S is perpendicular to the line segment
joining P and Q.

The line segment joining R and U is parallel to the line segment joining T
and Q.
Based on the above statements, which one of the following options is
CORRECT?
(A) The line segment joining R and T is parallel to the line segment joining Q and S
(B) The line segment joining T and Q is parallel to the line joining P and U
(C) The line segment joining R and P is perpendicular to the line segment joining U
and Q
(D) The line segment joining Q and S is perpendicular to the line segment joining R
and P
Page 9 of 36
Q.10
An ant is at the bottom-left corner of a grid (point P) as shown above. It aims to
move to the top-right corner of the grid. The ant moves only along the lines
marked in the grid such that the current distance to the top-right corner strictly
decreases.
Which one of the following is a part of a possible trajectory of the ant during
the movement?
(A)
(B)
(C)
(D)
Page 10 of 36
GATE 2022 Electrical Engineering (EE)
Q.11 – Q.35 Carry ONE mark Each
Q.11
The transfer function of a real system, 𝐻(𝑠), is given as:
𝐻 (𝑠) =
,
where 𝐴, 𝐵, 𝐶 and 𝐷 are positive constants. This system cannot operate as
(A)
low pass filter.
(B)
high pass filter.
(C)
band pass filter.
(D)
an integrator.
Q.12
For an ideal MOSFET biased in saturation, the magnitude of the small signal
current gain for a common drain amplifier is
(A)
0
(B)
1
(C)
100
(D)
infinite
Page 11 of 36
GATE 2022 Electrical Engineering (EE)
Q.13
The most commonly used relay, for the protection of an alternator against loss of
excitation, is
(A)
offset Mho relay.
(B)
over current relay.
(C)
differential relay.
(D)
Buchholz relay.
Q.14
The geometric mean radius of a conductor, having four equal strands with each strand
of radius ‘𝑟’, as shown in the figure below, is
r
(A)
4𝑟
(B)
1.414 𝑟
(C)
2𝑟
(D)
1.723 𝑟
Page 12 of 36
GATE 2022 Electrical Engineering (EE)
Q.15
The valid positive, negative and zero sequence impedances (in p.u.), respectively, for
a 220 kV, fully transposed three-phase transmission line, from the given choices are
(A)
1.1, 0.15 and 0.08
(B)
0.15, 0.15 and 0.35
(C)
0.2, 0.2 and 0.2
(D)
0.1, 0.3 and 0.1
Q.16
The steady state output (𝑉
(A)
saturate to +VDD
(B)
saturate to -VEE
(C)
become equal to 0.1 V
(D)
become equal to –0.1 V
), of the circuit shown below, will
Page 13 of 36
GATE 2022 Electrical Engineering (EE)
Q.17
The Bode magnitude plot of a first order stable system is constant with frequency.
The asymptotic value of the high frequency phase, for the system, is −180 . This
system has
(A)
one LHP pole and one RHP zero at the same frequency.
(B)
one LHP pole and one LHP zero at the same frequency.
(C)
two LHP poles and one RHP zero.
(D)
two RHP poles and one LHP zero.
Q.18
A balanced Wheatstone bridge 𝐴𝐵𝐶𝐷 has the following arm resistances:
𝑅
= 1 𝑘Ω ± 2.1% ; 𝑅
𝑅
= 300 Ω ± 0.4%. The value of 𝑅
(A)
30 Ω ± 3 Ω
(B)
30 Ω ± 0.9 Ω
(C)
3000 Ω ± 90 Ω
(D)
3000 Ω ± 3 Ω
= 100 Ω ± 0.5% ; 𝑅
is an unknown resistance;
and its accuracy is
Page 14 of 36
GATE 2022 Electrical Engineering (EE)
Q.19
The open loop transfer function of a unity gain negative feedback system is given by
𝐺 (𝑠) =
. The range of 𝑘 for which the system is stable, is
(A)
𝑘>3
(B)
𝑘<3
(C)
𝑘>5
(D)
𝑘<5
Q.20
Consider a 3 x 3 matrix 𝐴 whose (𝑖, 𝑗)-th element, 𝑎 , = (𝑖 − 𝑗) . Then the matrix 𝐴
will be
(A)
symmetric.
(B)
skew-symmetric.
(C)
unitary.
(D)
null.
Page 15 of 36
GATE 2022 Electrical Engineering (EE)
Q.21
In the circuit shown below, a three-phase star-connected unbalanced load is connected
to a balanced three-phase supply of 100√3 𝑉 with phase sequence 𝐴𝐵𝐶. The star
connected load has 𝑍 = 10 Ω and 𝑍 = 20∠60 Ω. The value of 𝑍 in Ω, for which
the voltage difference across the nodes 𝑛 and 𝑛′ is zero, is
(A)
20∠−30
(B)
20∠30
(C)
20∠−60
(D)
20∠60
Q.22
A charger supplies 100 W at 20 V for charging the battery of a laptop. The power
devices, used in the converter inside the charger, operate at a switching frequency of
200 kHz. Which power device is best suited for this purpose?
(A)
IGBT
(B)
Thyristor
(C)
MOSFET
(D)
BJT
Page 16 of 36
GATE 2022 Electrical Engineering (EE)
Q.23
A long conducting cylinder having a radius ‘b’ is placed along the z axis. The current
density is 𝐉 = J r z for the region r < b where r is the distance in the radial direction.
The magnetic field intensity (H) for the region inside the conductor (i.e. for r < b) is
(A)
J
r
4
(B)
J
r
3
(C)
J
r
5
(D)
J r
Q.24
The type of single-phase induction motor, expected to have the maximum power
factor during steady state running condition, is
(A)
split phase (resistance start).
(B)
shaded pole.
(C)
capacitor start.
(D)
capacitor start, capacitor run.
Page 17 of 36
GATE 2022 Electrical Engineering (EE)
Q.25
For the circuit shown below with ideal diodes, the output will be
(A)
𝑉
= 𝑉 for 𝑉 > 0
(B)
𝑉
= 𝑉 for 𝑉 < 0
(C)
𝑉
= −𝑉 for 𝑉 > 0
(D)
𝑉
= −𝑉 for 𝑉 < 0
Q.26
A MOD 2 and a MOD 5 up-counter when cascaded together results in a MOD ______
counter. (in integer)
Q.27
An inductor having a 𝑄-factor of 60 is connected in series with a capacitor having a 𝑄factor of 240. The overall 𝑄-factor of the circuit is ________. (round off to nearest
integer)
Page 18 of 36
GATE 2022 Electrical Engineering (EE)
Q.28
The network shown below has a resonant frequency of 150 kHz and a bandwidth of
600 Hz. The 𝑄-factor of the network is __________. (round off to nearest integer)
Q.29
The maximum clock frequency in MHz of a 4-stage ripple counter, utilizing flipflops, with each flip-flop having a propagation delay of 20 ns, is ___________.
(round off to one decimal place)
Q.30
If only 5% of the supplied power to a cable reaches the output terminal, the power loss
in the cable, in decibels, is _________. (round off to nearest integer)
Q.31
In the circuit shown below, the switch 𝑆 is closed at 𝑡 = 0. The magnitude of the steady
state voltage, in volts, across the 6 Ω resistor is _________. (round off to two decimal
places).
Page 19 of 36
GATE 2022 Electrical Engineering (EE)
Q.32
A single-phase full-bridge diode rectifier feeds a resistive load of 50 Ω from a 200 V,
50 Hz single phase AC supply. If the diodes are ideal, then the active power, in watts,
drawn by the load is _____________. (round off to nearest integer).
Q.33
The voltage at the input of an AC-DC rectifier is given by 𝑣(𝑡) = 230√2 sin 𝜔𝑡 where
𝜔 = 2𝜋 × 50 rad/s. The input current drawn by the rectifier is given by
𝑖 (𝑡) = 10 sin 𝜔𝑡 −
+ 4 sin 3𝜔𝑡 −
+ 3sin 5𝜔𝑡 −
.
The input power factor, (rounded off to two decimal places), is, _________________
lag.
Q.34
Two balanced three-phase loads, as shown in the figure, are connected to a 100√3 V,
three-phase, 50 Hz main supply. Given 𝑍 = (18 + 𝑗24) Ω and 𝑍 = (6 + 𝑗8) Ω . The
ammeter reading, in amperes, is _______. (round off to nearest integer)
Q.35
The frequencies of the stator and rotor currents flowing in a three-phase 8-pole
induction motor are 40 Hz and 1 Hz, respectively. The motor speed, in rpm, is
_________________. (round off to nearest integer)
Page 20 of 36
GATE 2022 Electrical Engineering (EE)
Q.36 – Q.65 Carry TWO marks Each
Q.36
The output impedance of a non-ideal operational amplifier is denoted by Z . The
variation in the magnitude of Z with increasing frequency, f, in the circuit shown
below, is best represented by
(A)
(B)
log(|Zout|)
log(f)
(C)
Page 21 of 36
GATE 2022 Electrical Engineering (EE)
(D)
Q.37
An LTI system is shown in the figure where
𝐺(𝑠) =
.
.
The steady state output of the system, to the input 𝑟(𝑡), is given as
𝑦(𝑡) = 𝑎 + 𝑏 𝑠𝑖𝑛(10𝑡 + 𝜃). The values of ‘𝑎’ and ‘𝑏’ will be
(A)
𝑎 = 1, 𝑏 = 10
(B)
𝑎 = 10, 𝑏 = 1
(C)
𝑎 = 1, 𝑏 = 100
(D)
𝑎 = 100, 𝑏 = 1
Page 22 of 36
GATE 2022 Electrical Engineering (EE)
Q.38
The open loop transfer function of a unity gain negative feedback system is given
as
𝐺(𝑠) =
(
)
.
The Nyquist contour in the 𝑠-plane encloses the entire right half plane and a small
neighbourhood around the origin in the left half plane, as shown in the figure below.
The number of encirclements of the point (−1 + 𝑗0) by the Nyquist plot of 𝐺 (𝑠),
corresponding to the Nyquist contour, is denoted as 𝑁. Then 𝑁 equals to
(A)
0
(B)
1
(C)
2
(D)
3
Page 23 of 36
GATE 2022 Electrical Engineering (EE)
Q.39
The damping ratio and undamped natural frequency of a closed loop system as
shown in the figure, are denoted as 𝜁 and 𝜔 , respectively. The values of 𝜁 and 𝜔
are
(A)
𝜁 = 0.5 and 𝜔 = 10 rad/s
(B)
𝜁 = 0.1 and 𝜔 = 10 rad/s
(C)
𝜁 = 0.707 and 𝜔 = 10 rad/s
(D)
𝜁 = 0.707 and 𝜔 = 100 rad/s
Q.40
𝑒 denotes the exponential of a square matrix A. Suppose 𝜆 is an eigenvalue and
𝑣 is the corresponding eigen-vector of matrix A.
Consider the following two statements:
Statement 1: 𝑒 is an eigenvalue of 𝑒 .
Statement 2: 𝑣 is an eigen-vector of 𝑒 .
Which one of the following options is correct?
(A)
Statement 1 is true and statement 2 is false.
(B)
Statement 1 is false and statement 2 is true.
(C)
Both the statements are correct.
(D)
Both the statements are false.
Page 24 of 36
GATE 2022 Electrical Engineering (EE)
Q.41
Let 𝑓(𝑥) = ∫ 𝑒 (𝑡 − 1)(𝑡 − 2)𝑑𝑡. Then 𝑓(𝑥) decreases in the interval
(A)
𝑥 ∈ (1,2)
(B)
𝑥 ∈ (2,3)
(C)
𝑥 ∈ (0,1)
(D)
𝑥 ∈ (0.5,1)
Q.42
1 0
Consider a matrix 𝐴 = 0 4
0 1
0
−2 .
1
The matrix A satisfies the equation 6𝐴
scalars and 𝐼 is the identity matrix.
= 𝐴 + 𝑐𝐴 + 𝑑𝐼, where 𝑐 and 𝑑 are
Then (𝑐 + 𝑑) is equal to
(A)
5
(B)
17
(C)
−6
(D)
11
Page 25 of 36
GATE 2022 Electrical Engineering (EE)
Q.43
The fuel cost functions in rupees/hour for two 600 MW thermal power plants are
given by
Plant 1: 𝐶 = 350 + 6𝑃 + 0.004𝑃
Plant 2: 𝐶 = 450 + 𝑎𝑃 + 0.003𝑃
where 𝑃 and 𝑃 are power generated by plant 1 and plant 2, respectively, in MW
and 𝑎 is constant. The incremental cost of power (𝜆) is 8 rupees per MWh. The two
thermal power plants together meet a total power demand of 550 MW. The optimal
generation of plant 1 and plant 2 in MW, respectively, are
(A)
200, 350
(B)
250, 300
(C)
325, 225
(D)
350, 200
Page 26 of 36
GATE 2022 Electrical Engineering (EE)
Q.44
The current gain (Iout/Iin) in the circuit with an ideal current amplifier given below
is
Cf
Cc
Iin
∞
Iout
(A)
𝐶
𝐶
(B)
−𝐶
𝐶
(C)
𝐶
𝐶
(D)
−𝐶
𝐶
Q.45
If the magnetic field intensity (H) in a conducting region is given by the expression,
𝐇 = 𝑥 ı̂ + 𝑥 𝑦 ȷ̂ + 𝑥 𝑦 𝑧 k A/m. The magnitude of the current density, in
A/m2, at 𝑥 = 1 m, 𝑦 = 2 m, and 𝑧 = 1 m, is
(A)
8
(B)
12
(C)
16
(D)
20
Page 27 of 36
GATE 2022 Electrical Engineering (EE)
Q.46
Let a causal LTI system be governed by the following differential equation
𝑦(𝑡) +
= 2𝑥 (𝑡 ), where 𝑥(𝑡) and 𝑦(𝑡) are the input and output respectively.
Its impulse response is
(A)
2𝑒
𝑢(𝑡)
(B)
2𝑒
𝑢(𝑡)
(C)
8𝑒
𝑢(𝑡)
(D)
8𝑒
𝑢(𝑡)
Q.47
Let an input 𝑥 (𝑡 ) = 2 sin(10𝜋𝑡) + 5cos(15𝜋𝑡) + 7sin(42𝜋𝑡) + 4cos(45𝜋𝑡) is
passed through an LTI system having an impulse response,
ℎ(𝑡) = 2
(
)
cos(40𝜋𝑡).
The output of the system is
(A)
2 sin(10𝜋𝑡) + 5𝑐𝑜𝑠 (15𝜋𝑡)
(B)
5𝑐𝑜𝑠 (15𝜋𝑡) + 7 sin(42𝜋𝑡)
(C)
7 sin(42𝜋𝑡) + 4𝑐𝑜𝑠 (45𝜋𝑡)
(D)
2 sin(10𝜋𝑡) + 4𝑐𝑜𝑠 (45𝜋𝑡)
Page 28 of 36
GATE 2022 Electrical Engineering (EE)
Q.48
Consider the system as shown below
where 𝑦(𝑡) = 𝑥(𝑒 ). The system is
(A)
linear and causal.
(B)
linear and non-causal.
(C)
non-linear and causal.
(D)
non-linear and non-causal.
Q.49
The discrete time Fourier series representation of a signal 𝑥[𝑛] with period 𝑁 is
⁄ )
written as 𝑥[𝑛] = ∑
𝑎 𝑒 (
. A discrete time periodic signal with period
𝑁 = 3, has the non-zero Fourier series coefficients: 𝑎 = 2 and 𝑎 = 1. The
signal is
(A)
(B)
(C)
(D)
2 + 2𝑒
cos
2𝜋
𝑛
6
1 + 2𝑒
cos
2𝜋
𝑛
6
1 + 2𝑒
cos
2𝜋
𝑛
6
2 + 2𝑒
cos
2𝜋
𝑛
6
Page 29 of 36
GATE 2022 Electrical Engineering (EE)
Q.50
Let, f(𝑥, 𝑦, 𝑧) = 4𝑥 + 7𝑥𝑦 + 3𝑥𝑧 . The direction in which the function 𝑓(𝑥, 𝑦, 𝑧)
increases most rapidly at point 𝑃 = (1,0,2) is
(A)
20𝚤̂ + 7𝚥̂
(B)
20𝚤̂ + 7𝚥̂ + 12𝑘
(C)
20𝚤̂ + 12𝑘
(D)
20𝚤̂
Q.51
Let 𝑅 be a region in the first quadrant of the 𝑥𝑦 plane enclosed by a closed curve 𝐶
considered in counter-clockwise direction. Which of the following expressions does
not represent the area of the region 𝑅?
(A)
𝑑𝑥𝑑𝑦
(B)
𝑥𝑑𝑦
(C)
(D)
𝑦𝑑𝑥
1
2
(𝑥𝑑𝑦 − 𝑦𝑑𝑥)
Page 30 of 36
GATE 2022 Electrical Engineering (EE)
Q.52
Let 𝐸⃗ (𝑥, 𝑦, 𝑧) = 2𝑥 𝚤̂ + 5𝑦𝚥̂ + 3𝑧𝑘. The value of ∭ (∇⃗ ⋅ 𝐸⃗ )𝑑𝑉 , where 𝑉 is the
volume enclosed by the unit cube defined by 0 ≤ 𝑥 ≤ 1, 0 ≤ 𝑦 ≤ 1, 𝑎𝑛𝑑 0 ≤ 𝑧 ≤
1, is
(A)
3
(B)
8
(C)
10
(D)
5
Page 31 of 36
GATE 2022 Electrical Engineering (EE)
Q.53
As shown in the figure below, two concentric conducting spherical shells, centered
at r = 0 and having radii r = c and r = d are maintained at potentials such that
the potential V(r) at r = c is V and V(r) at r = d is V . Assume that V(r) depends
only on r, where r is the radial distance. The expression for V(r) in the region
between r = c and r = d is
(A)
(B)
(C)
(D)
V(r) =
c d (V − V ) V c + V d − 2 V d
−
(d − c) r
d−c
V(r) =
c d (V − V ) V d − V c
+
(d − c) r
d−c
V(r) =
c d (V − V ) V c − V c
−
(d − c) r
d−c
V(r) =
c d (V − V ) V c − V c
−
(d − c) r
d−c
Page 32 of 36
GATE 2022 Electrical Engineering (EE)
Q.54
Let the probability density function of a random variable 𝑥 be given as
𝑓(𝑥) = 𝑎𝑒
| |
The value of ‘a’ is __________.
Q.55
In the circuit shown below, the magnitude of the voltage V in volts, across the 8 𝑘Ω
resistor is ______________. (round off to nearest integer)
Q.56
Two generating units rated for 250 MW and 400 MW have governor speed
regulations of 6% and 6.4%, respectively, from no load to full load. Both the
generating units are operating in parallel to share a load of 500 MW. Assuming free
governor action, the load shared in MW, by the 250 MW generating unit is
_________. (round off to nearest integer)
Q.57
A 20 MVA, 11.2 kV, 4-pole, 50 Hz alternator has an inertia constant of
15 MJ/MVA. If the input and output powers of the alternator are 15 MW and
10 MW, respectively, the angular acceleration in mechanical degree/s2 is
__________. (round off to nearest integer)
Page 33 of 36
GATE 2022 Electrical Engineering (EE)
Q.58
Consider an ideal full-bridge single-phase DC-AC inverter with a DC bus voltage
magnitude of 1000 V. The inverter output voltage 𝑣(𝑡) shown below, is obtained
when diagonal switches of the inverter are switched with 50 % duty cycle. The
inverter feeds a load with a sinusoidal current given by, 𝑖(𝑡) = 10 sin(𝜔𝑡 − ) A,
where 𝜔 =
. The active power, in watts, delivered to the load is _________.
(round off to nearest integer)
Q.59
For the ideal AC-DC rectifier circuit shown in the figure below, the load current
magnitude is Idc = 15 A and is ripple free. The thyristors are fired with a delay angle
of 45o. The amplitude of the fundamental component of the source current, in
amperes, is __________. (round off to two decimal places)
Q.60
A 3-phase grid-connected voltage source converter with DC link voltage of 1000 V
is switched using sinusoidal Pulse Width Modulation (PWM) technique. If the grid
phase current is 10 A and the 3-phase complex power supplied by the converter is
given by (−4000 − 𝑗3000) VA, then the modulation index used in sinusoidal
PWM is ___________. (round off to two decimal places)
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GATE 2022 Electrical Engineering (EE)
Q.61
The steady state current flowing through the inductor of a DC-DC buck boost
converter is given in the figure below. If the peak-to-peak ripple in the output
voltage of the converter is 1 V, then the value of the output capacitor, in µF, is
_______________. (round off to nearest integer)
Q.62
A 280 V, separately excited DC motor with armature resistance of 1 Ω and constant
field excitation drives a load. The load torque is proportional to the speed. The
motor draws a current of 30 A when running at a speed of 1000 rpm. Neglect
frictional losses in the motor. The speed, in rpm, at which the motor will run, if an
additional resistance of value 10 Ω is connected in series with the armature, is
__________. (round off to nearest integer)
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GATE 2022 Electrical Engineering (EE)
Q.63
A 4-pole induction motor with inertia of 0.1 kg-m2 drives a constant load torque of
2 Nm. The speed of the motor is increased linearly from 1000 rpm to 1500 rpm in
4 seconds as shown in the figure below. Neglect losses in the motor. The energy, in
joules, consumed by the motor during the speed change is ____________. (round
off to nearest integer)
Q.64
A star-connected 3-phase, 400 V, 50 kVA, 50 Hz synchronous motor has a
synchronous reactance of 1 ohm per phase with negligible armature resistance. The
shaft load on the motor is 10 kW while the power factor is 0.8 leading. The loss in
the motor is 2 kW. The magnitude of the per phase excitation emf of the motor, in
volts, is __________. (round off to nearest integer).
Q.65
A 3-phase, 415 V, 4-pole, 50 Hz induction motor draws 5 times the rated current at
rated voltage at starting. It is required to bring down the starting current from the
supply to 2 times of the rated current using a 3-phase autotransformer. If the
magnetizing impedance of the induction motor and no load current of the
autotransformer is neglected, then the transformation ratio of the autotransformer is
given by ____________. (round off to two decimal places).
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